package com.estronger.shopmanage.view.textview;

import android.content.Context;
import android.graphics.Paint;
import android.support.annotation.Nullable;
import android.text.TextUtils;
import android.util.AttributeSet;
import android.view.ViewTreeObserver;
import android.widget.TextView;

public class CYTextView extends TextView {


    public CYTextView(Context context) {
        super(context);
    }

    public CYTextView(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
    }

    public CYTextView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    public CYTextView(Context context, @Nullable AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
    }

    public void setNeatFormat() {
        this.getViewTreeObserver().addOnGlobalLayoutListener(new OnTvGlobalLayoutListener(this));
    }
    private class OnTvGlobalLayoutListener implements ViewTreeObserver.OnGlobalLayoutListener {
        TextView mText;
        public  OnTvGlobalLayoutListener(TextView mText){
            this.mText = mText;
        }
        @Override
        public void onGlobalLayout() {
            mText.getViewTreeObserver().removeOnGlobalLayoutListener(this);
            final String newText = autoSplitText(mText);
            if (!TextUtils.isEmpty(newText)) {
                mText.setText(newText);
            }
        }
    }
    private String autoSplitText(final TextView tv) {
        final String rawText = tv.getText().toString(); //原始文本
        final Paint tvPaint = tv.getPaint(); //paint，包含字体等信息
        final float tvWidth = tv.getWidth() - tv.getPaddingLeft() - tv.getPaddingRight(); //控件可用宽度
        //将原始文本按行拆分
        String [] rawTextLines = rawText.replaceAll("\r", "").split("\n");
        StringBuilder sbNewText = new StringBuilder();
        for (String rawTextLine : rawTextLines) {
            if (tvPaint.measureText(rawTextLine) <= tvWidth) {
                //如果整行宽度在控件可用宽度之内，就不处理了
                sbNewText.append(rawTextLine);
            } else {
                //如果整行宽度超过控件可用宽度，则按字符测量，在超过可用宽度的前一个字符处手动换行
                float lineWidth = 0;
                for (int cnt = 0; cnt != rawTextLine.length(); ++cnt) {
                    char ch = rawTextLine.charAt(cnt);
                    lineWidth += tvPaint.measureText(String.valueOf(ch));
                    if (lineWidth <= tvWidth) {
                        sbNewText.append(ch);
                    } else {
                        sbNewText.append("\n");
                        lineWidth = 0;
                        --cnt;
                    }
                }
            }
            sbNewText.append("\n");
        }
        //把结尾多余的\n去掉
        if (!rawText.endsWith("\n")) {
            sbNewText.deleteCharAt(sbNewText.length() - 1);
        }
        return sbNewText.toString();
    }
}
